Transmitter beamforming at base station with partial channel information and ue feedback

ABSTRACT

Methods and systems of obtaining a beamforming matrix, the method comprising inputting PMI feedback from a user equipment (UE), inputting partial channel estimation derived from sounding reference signal (SRS) switching, and composing a precoding matrix using the PMI feedback and partial channel estimation.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.17/020,562, filed Sep. 14, 2020, which claims the benefit of U.S.Provisional Patent Application No. 63/055,507, filed Jul. 23, 2020 inthe United States Patent and Trademark Office, the entire contents ofboth/each of which are incorporated herein by reference.

FIELD

The present disclosure is generally related to wireless communicationsystems. In particular, the present disclosure is related to a systemsand methods for transmitter beamforming at base station with partialchannel information and UE feedback.

BACKGROUND

In cellular systems (e.g., LTE and 5G NR), gNB typically decides its Txdigital beamforming precoding matrix using one of the following twomethods: Uplink channel estimation from sounding reference signal (SRS)and precoding matrix indicator (PMI) feedback from UE. Since UEtypically has more receive (Rx) antenna ports than transmit (Tx) antennaports, SRS switching is introduced in new radio (NR) standard so thatthe UE can sweep different antenna ports during the transmission of SRS.

gNB beamforming based on uplink (UL) SRS channel estimation (CE) relieson the UE capability of SRS switching. Some UEs may only have partialcapability of SRS switching, e.g., having 4 Rx antenna ports but onlysupporting 1T2R SRS switching. On the other hand, gNB beamforming basedon UE PMI feedback is limited by the codebook design. Due to theconstraint of signaling overhead, the PMI codebook has a finite sizelimit, which results in aggressive quantization in the beamformingvectors.

SUMMARY

According to some embodiments, a method of obtaining a beamformingmatrix, the method comprising: inputting partial channel estimationderived from sounding reference signal (SRS) switching; inputtingprecoding matrix indicator (PMI) feedback from a user equipment (UE);and composing a beamforming matrix using the PMI feedback and partialchannel estimation.

According to one embodiment, a first set of columns of the precodingmatrix are obtained from the partial channel estimation and a second setof columns of the precoding matrix are obtained from the PMI feedback.

According to one embodiment, the PMI feedback is obtained by projectinga matrix indicated by the PMI feedback into a sub-space that isorthogonal to columns obtained from the partial channel estimation.

According to one embodiment, performing a singular value decomposition(SVD) for a channel matrix.

According to one embodiment, calculating a projection matrix using theprecoding matrix indicator (PMI) feedback.

According to one embodiment, calculating a residual matrix using theprecoding matrix indicator (PMI) feedback.

According to one embodiment, performing a singular value decomposition(SVD) for the residual matrix.

According to one embodiment, calculating a transformation matrix usingof the PMI feedback.

According to one embodiment, selecting a first set of columns of asingular matrix in composing the precoding matrix.

A system for obtaining a beamforming matrix, the system comprising:

a processor; and a memory storing non-transitory processor-executableinstructions that, when executed by the processor, cause the processorto: input partial channel estimation derived from sounding referencesignal (SRS) switching; input precoding matrix indicator (PMI) feedback;compose a precoding matrix using the PMI feedback and partial channelestimation.

According to one embodiment, a first set of columns of the precodingmatrix is obtained from the partial channel estimation and a second setof columns of the precoding matrix are obtained from the PMI feedback.

According to one embodiment, the PMI feedback is obtained by projectinga matrix indicated by the PMI feedback into a sub-space that isorthogonal to columns obtained from the partial channel estimation.

According to one embodiment, performing a singular value decomposition(SVD) for a channel matrix.

According to one embodiment, calculating a projection matrix using theprecoding matrix indicator (PMI) feedback.

According to one embodiment, calculating a residual matrix using theprecoding matrix indicator (PMI) feedback.

According to one embodiment, performing a singular value decomposition(SVD) for the residual matrix.

According to one embodiment, calculating a transformation matrix usingof the PMI feedback.

According to one embodiment, selecting a first set of columns of asingular matrix in composing the precoding matrix.

A method of composing a final beamforming matrix, the method comprising:performing a first singular value decomposition (SVD) of a partialchannel estimation matrix to obtain a first singular matrix, the partialchannel estimation matrix being based on one or more uplink soundingreference signals (SRS) or one or more other reference signals;obtaining a first beamforming matrix based on precoding matrix indicator(PMI) feedback; calculating a projection of the first beamforming matrixto the first singular vector; performing, after removing the projectionof the first beamforming matrix to the first singular matrix, a secondSVD of a residual of the first beamforming matrix to obtain a secondsingular matrix; and using, a first set of columns of the first singularmatrix and the second singular matrix to compose the final beamformingmatrix.

A non-transitory computer-readable medium comprising instructions forderiving a beamforming matrix, wherein execution of the instructions byone or more processors causes the one or more processors to carry outthe steps of: estimating a partial channel based on one or more receivedsounding reference signals (SRS); deriving a first beamforming matrixbased on a received precoding matrix indicator (PMI) feedback; andderiving a second beamforming matrix based on the partial channel andthe first beamforming matrix.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainembodiments of the present disclosure will be more apparent from thefollowing detailed description, taken in conjunction with theaccompanying drawings, in which:

FIG. 1 illustrates a diagram of a user equipment (UE), according to someembodiments;

FIG. 2 illustrates a flowchart for deriving a beamforming matrix,according to some embodiments;

FIG. 3 illustrates a diagram for composing a precoding matrix, accordingto some embodiments;

FIG. 4 illustrates a flowchart for composing a precoding matrix,according to some embodiments; and

FIG. 5 illustrates a block diagram of an electronic device in a networkenvironment, according to one embodiment.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present disclosure are described indetail with reference to the accompanying drawings. It should be notedthat the same elements will be designated by the same reference numeralsalthough they are shown in different drawings. In the followingdescription, specific details such as detailed configurations andcomponents are merely provided to assist with the overall understandingof the embodiments of the present disclosure. Therefore, it should beapparent to those skilled in the art that various changes andmodifications of the embodiments described herein may be made withoutdeparting from the scope of the present disclosure. In addition,descriptions of well-known functions and constructions are omitted forclarity and conciseness. The terms described below are terms defined inconsideration of the functions in the present disclosure, and may bedifferent according to users, intentions of the users, or customs.Therefore, the definitions of the terms should be determined based onthe contents throughout this specification.

The present disclosure may have various modifications and variousembodiments, among which embodiments are described below in detail withreference to the accompanying drawings. However, it should be understoodthat the present disclosure is not limited to the embodiments, butincludes all modifications, equivalents, and alternatives within thescope of the present disclosure.

Although the terms including an ordinal number such as first, second,etc. may be used for describing various elements, the structuralelements are not restricted by the terms. The terms are only used todistinguish one element from another element. For example, withoutdeparting from the scope of the present disclosure, a first structuralelement may be referred to as a second structural element. Similarly,the second structural element may also be referred to as the firststructural element. As used herein, the term “and/or” includes any andall combinations of one or more associated items.

The terms used herein are merely used to describe various embodiments ofthe present disclosure but are not intended to limit the presentdisclosure. Singular forms are intended to include plural forms unlessthe context clearly indicates otherwise. In the present disclosure, itshould be understood that the terms “include” or “have” indicateexistence of a feature, a number, a step, an operation, a structuralelement, parts, or a combination thereof, and do not exclude theexistence or probability of the addition of one or more other features,numerals, steps, operations, structural elements, parts, or combinationsthereof.

Unless defined differently, all terms used herein have the same meaningsas those understood by a person skilled in the art to which the presentdisclosure belongs. Terms such as those defined in a generally useddictionary are to be interpreted to have the same meanings as thecontextual meanings in the relevant field of art, and are not to beinterpreted to have ideal or excessively formal meanings unless clearlydefined in the present disclosure.

The electronic device according to one embodiment may be one of varioustypes of electronic devices. The electronic devices may include, forexample, a portable communication device (e.g., a smart phone), acomputer, a portable multimedia device, a portable medical device, acamera, a wearable device, or a home appliance. According to oneembodiment of the disclosure, an electronic device is not limited tothose described above.

The terms used in the present disclosure are not intended to limit thepresent disclosure but are intended to include various changes,equivalents, or replacements for a corresponding embodiment. With regardto the descriptions of the accompanying drawings, similar referencenumerals may be used to refer to similar or related elements. A singularform of a noun corresponding to an item may include one or more of thethings, unless the relevant context clearly indicates otherwise. As usedherein, each of such phrases as “A or B,” “at least one of A and B,” “atleast one of A or B,” “A, B, or C,” “at least one of A, B, and C,” and“at least one of A, B, or C,” may include all possible combinations ofthe items enumerated together in a corresponding one of the phrases. Asused herein, terms such as “1^(st),” “2nd,” “first,” and “second” may beused to distinguish a corresponding component from another component,but are not intended to limit the components in other aspects (e.g.,importance or order). It is intended that if an element (e.g., a firstelement) is referred to, with or without the term “operatively” or“communicatively”, as “coupled with,” “coupled to,” “connected with,” or“connected to” another element (e.g., a second element), it indicatesthat the element may be coupled with the other element directly (e.g.,wired), wirelessly, or via a third element.

As used herein, the term “module” may include a unit implemented inhardware, software, or firmware, and may interchangeably be used withother terms, for example, “logic,” “logic block,” “part,” and“circuitry.” A module may be a single integral component, or a minimumunit or part thereof, adapted to perform one or more functions. Forexample, according to one embodiment, a module may be implemented in aform of an application-specific integrated circuit (ASIC).

This disclosure is directed, at least in part, to methods and systems toderive one or more gNB beamforming matrices based on UE precoding matrixindicator (PMI) feedback and SRS channel estimation with partial SRSswitching. Beamforming or spatial filtering is a signal processingtechnique used in sensor arrays for directional signal transmission orreception. This may be achieved by combining elements in an antenna portarray in such a way that signals at particular angles experienceconstructive interference while others experience destructiveinterference. Beamforming may be used at both the transmitting andreceiving ends in order to achieve spatial selectivity. Precoding may bea form of beamforming to support multi-stream (or multi-layer)transmission in multi-antenna port wireless communications. Insingle-stream beamforming, the same signal may be emitted from each ofthe transmit antenna ports with appropriate weighting (phase and gain)such that the signal power is maximized at the receiver output.Precoding may allow for greater flexibility since gNB can assigndifferent powers and phases to different antennas and also to differentparts of the frequency bands (e.g., subcarriers). When the receiver hasmultiple antenna ports, multi-stream transmission may be used tomaximize the throughput. In some embodiments of the present invention,the terms “precoding” may be used interchangeably with “beamforming” or“digital beamforming.”

FIG. 1 illustrates a diagram of a user equipment (UE) 102 according tosome embodiments. UE 102 may comprise one, two, three or moretransmit/receive (Tx/Rx) antenna ports (e.g. 104, 106) and one, two,three or more receive (Rx) antenna ports (e.g., 108 and 110). UE 102 maycomprise more or less transmit and receive antenna ports than depictedin FIG. 1. UE 102 may operate within a downlink (DL) system, withtransmissions from gNB and reception at UE 102, where there are N_(T)transmit antenna ports at gNB side and N_(R)=4 receive antenna ports atUE 102 side. In uplink, UE 102 may only be able to support 1T2R SRSswitching, which means UE 102 can only transmit SRS from 1 antenna portat a time, either 104 or 106, and can sweep 2 antenna ports over time,104 and 106. In other words, gNB can get channel estimation from 2 UEantenna ports. Other embodiments are disclosed herein, for example,1T/1R (e.g., no dynamic switching), 1T/3R, 2T/3R, 2T/2R, 1T/4R, 2T/4R,and 3T/4R. The embodiments of this invention may be applied in all caseswhere gNB only obtains channel information from a portion of the totalamount of UE antenna ports that will receive data.

This application discloses methods and systems of Tx beamforming orprecoding schemes at the gNB side in a special case when the UE 102 hasmultiple receive antenna ports (e.g., Rx antenna ports 106, 108, and110) and may perform both 1 transmit/2 receive (1T2R) sounding referencesignal (SRS) switching and precoding matrix indicator (PMI) feedback. Inthis case, gNB may receive (1) the downlink channel estimation to 2among 4 UE Rx antenna ports based on channel reciprocity and (2) PMIfeedback, which may be a noisy, quantized and delayed version of theoptimum Tx beamforming. In this disclosure, the gNB may combine the twogroups of information to derive a precoding matrix.

This application discloses a heuristic solution to combine the partialchannel matrix from reciprocity and PMI feedback, which may be used inthe case when channel rank is not known.

Turning now to FIG. 2, a flowchart 200 for composing the precodingmatrix is depicted. If the downlink (DL) channel matrix is written as:

$\begin{matrix}{H = {\begin{bmatrix}h_{1} \\h_{2} \\h_{3} \\h_{4}\end{bmatrix} = \begin{bmatrix}H_{t} \\H_{b}\end{bmatrix}}} & (1)\end{matrix}$

$H_{t} = \begin{bmatrix}h_{1} \\h_{2}\end{bmatrix}$

is the top part of the channel matrix and

$H_{b} = \begin{bmatrix}h_{3} \\h_{4}\end{bmatrix}$

is the bottom part of the channel matrix. gNB may obtain Ĥ_(t) (anestimation of H_(t)), which may equal H_(t) and E₁ (the channelestimation error), from 1T2R SRS switching based on Tx/Rx reciprocity,where:

Ĥ _(t) =H _(t) +E ₁  (2)

One or more orthogonal frequency-division multiplexing (OFDM) channelestimation algorithms may be used to obtain the SRS channel estimationH_(t) at gNB. gNB may also receive the PMI feedback transmitted from theUE 102, which may inform the gNB regarding the recommended precodingmatrix based on the UE's 102 channel estimation and one or morecodebooks at gNB. In the present disclosure, channel H_(t) may be usedinterchangeably with the estimated channel Ĥ_(t) and vice versa.

The SVD of H_(t) may be written as:

H _(t) =Ũ{tilde over (Σ)}{tilde over (V)} ^(H)  (3)

where Ũ: 2×{tilde over (L)}, Σ: {tilde over (L)}×{tilde over (L)}, V:N_(T)×{tilde over (L)}. L is the rank of H_(t).

The steps in flowchart 200 may be employed when the rank of channel H isunknown, but the rank of the PMI feedback is known (e.g., {tilde over(L)}≤L_(PMI)≤L, where L is the rank of H, L_(PMI) is the rank ofW_(PMI), and {tilde over (L)} is the rank of Ĥ_(t)). The PMI feedbackmay relate to all of antennas 104, 106, 108, 110 such that the rank ofW_(PMI) is equal to or smaller than the rank of H. The precoding matrixdefined by the precoding matrix indicator may be defined as W_(PMI). Inthe 3rd Generation Partnership Project (3GPP) specifications, codebookscontain many beamforming/precoding matrices. When gNB receives PMIfeedback from the UE, gNB may look up the appropriate matrices to use incommunicate with the UE.

At step 202, a singular value decomposition (SVD) for Ĥ_(t) may beperformed in order to obtain its right singular matrix {tilde over (V)}.The SVD of Ĥ_(t) may be obtained, accordingly: Ĥ_(t)=Ũ{tilde over(Σ)}{tilde over (V)}^(H). In other embodiments, left singular matrices(e.g. Ũ) may be used instead of right singular matrices. {tilde over(V)}^(H), a Hermitian matrix may be derived by taking the transpose of{tilde over (V)} then taking the complex conjugate of each entry.Therefore, once {tilde over (V)} is known, {tilde over (V)}^(H) may bederived and vice versa. This is true for all Hermitian matrices.

At step 204, the projection of W_(pmi) into {tilde over (V)} may becalculated accordingly: W_(prj)={tilde over (V)}{tilde over(V)}^(H)W_(pmi). Then the residual of W_(pmi) may be calculatedaccordingly: W_(res)=W_(pmi)−W_(prj).

At step 206, a SVD for W_(res) ^(H) may be performed accordingly:W_(res) ^(H)=Ũ{tilde over (D)}{tilde over (V)}^(H) and its rightsingular matrix {circumflex over (V)} may be obtained. In other words, aSVD of the residual of a PMI feedback-based precoding matrix may bederived after removing its projection to {tilde over (V)} (e.g. SVD forW_(pmi) ^(H)−{tilde over (T)}{tilde over (V)}^(H)). {circumflex over(D)} may be defined as a diagonal matrix. Û may be defined as a leftsingular matrix, while {circumflex over (V)}^(H) may be defined as theright singular matrix. In other embodiments, a SVD for W_(res) may beperformed, in order to obtain and use the left singular matrix{circumflex over (V)}, accordingly: W_(res)={circumflex over(V)}{circumflex over (D)}Û^(H).

At step 208, the first L_(PMI)−{tilde over (L)} columns of V may beselected. L_(PMI) may be defined as the rank of W_(pmi), which isfeedback by the UE using rank indicator (RI). {tilde over (L)} may bedefined as the rank of Ĥ_(t). The precoding/beamforming matrix Ŵ may becomposed by horizontally concatenating the matrix {tilde over (V)} andthe first L_(PMI)−{tilde over (L)} columns of {circumflex over (V)}accordingly: Ŵ=[{acute over (V)} {circumflex over (V)}(:,1:L_(PMI)−{tilde over (L)})], where the first “:” means all rows of{circumflex over (V)} and “1: L_(PMI)−{tilde over (L)}” means fromcolumn 1 to column L_(PMI)−{tilde over (L)} of {circumflex over (V)}. Inthis way, the precoding matrix Ŵ is a combination representing the SRSinformation with {tilde over (V)} and the PMI information with {tildeover (V)}. In order to horizontally concatenate two matrices, theyshould have the same amount of rows, which is likely the case withmatrices {tilde over (V)} and {circumflex over (V)}. However, the numberof columns between matrices {tilde over (V)} and {circumflex over (V)}may vary. Since each matrix column may represent a UE antenna port, itis advantageous to select L_(PMI)−{tilde over (L)} columns from{circumflex over (V)} to cause the rank of the precoding/beamformingmatrix Ŵ to equal that of channel H (e.g. the number of UE antennaports). In other embodiments, the matrices {tilde over (V)} and{circumflex over (V)} may be concatenated vertically.

There are various methods to select columns from {circumflex over (V)}.Selecting the first L_(PMI)−{tilde over (L)} columns is just one of themany ways. The left-side columns, right side columns, middle columns orany combination may be selected. The columns that have a large or alargest correlation with W_(pmi) or the columns that most accuratelydescribe the channel may be selected. Alternatively, the columns may bechosen randomly or based on convenience or speed of processing. In atleast the case where L_(PMI)<{tilde over (L)}, the first L_(PMI) columnsof {tilde over (V)} may be selected as {tilde over (V)} may not sufferfrom quantization loss related to codebook constraints because one ormore orthogonal frequency-division multiplexing (OFDM) channelestimation algorithms was likely used to obtain the SRS channelestimation H_(t). This is because the, all the columns {circumflex over(V)} may be selected as {circumflex over (V)} may contain more completechannel information in spite of possible noise and distortion caused byquantization. Any another combination of the columns of {tilde over (V)}and {circumflex over (V)} may be selected as the final beamformingmatrix. These systems and methods are helpful in situations whereL_(PMI)<{tilde over (L)} because the UE or one or more UE antenna portshas not received CSI-RS from gNB, is malfunctioning, is down formaintenance, is experiencing interference or noise, and/or is notproviding complete PMI feedback for any other reason.

This method could also be used in other systems such as Long TermEvolution (LTE), where the base station can obtain both partial channelinformation and the precoding matrix from UE feedback to derive thefinal beamforming matrix.

Turning now to FIG. 3, an illustration 300 is shown of how the UE 102and gNB 306 may communicate with each other to derive the finalbeamforming matrix. The UE 102 may transmit SRS 304 (e.g. relating toantenna port 104) from the first antenna port 104 to the gNB 306. ThegNB 306 may then estimate the SRS channel Ĥ₁ 308. Then, the UE 102 maytransmit the SRS 310 (e.g. relating to antenna port 106) from the secondantenna port 106 to the gNB 306, where the gNB 306 estimates the SRSchannel Ĥ₂ to obtain Ĥ_(t)=[Ĥ₁ Ĥ₂] 312. The gNB 306 may transmit CSI-RSfrom all or some gNB N_(T) antenna ports 314 to all receive antennaports of the UE 102, where the UE 102 may estimate the CSI-RS channeland calculate PMI 316. UE 102 may then transmit feedback PMI 318 to thegNB 306, where the gNB 306 may utilize the feedback PMI 318 to derivethe precoding matrix W_(pmi) 320. Then gNB 306 may derive beamformingmatrix Ŵ 322 according any of the methods and/or systems disclosed inthis application.

Turning now to FIG. 4, a flowchart 400 for composing a precoding matrixis depicted. At step 402, a partial channel estimation may be estimatedfrom SRS information, for example, at gNB 306. The partial channel maycomprise a top, bottom, middle portion or any other group of a channel.

At step 404, PMI feedback from a user equipment (UE) is input, forexample, at gNB 306. This PMI feedback may be used by gNB 306 to producea PMI precoding matrix based on one or more codebooks.

At step 406, using the PMI feedback and partial channel estimation, aprecoding matrix may be composed, for example, at gNB 306. The precodingmatrix may be used to more efficiently send transmissions from gNB 306to UE 102. The steps in this flowchart may be used in conjunction withany of the methods and steps disclosed in the application.

FIG. 5 illustrates a block diagram of an electronic device 501 in anetwork environment 500, according to one embodiment. Referring to FIG.5, the electronic device 501 in the network environment 500 maycommunicate with another electronic device 502 via a first network 598(e.g., a short-range wireless communication network), or anotherelectronic device 504 or a server 508 via a second network 599 (e.g., along-range wireless communication network). The electronic device 501may also communicate with the electronic device 504 via the server 508.The electronic device 501 may include a processor 520, a memory 530, aninput device 550, a sound output device 555, a display device 560, anaudio module 570, a sensor module 576, an interface 577, a haptic module579, a camera module 580, a power management module 588, a battery 589,a communication module 590, a subscriber identification module (SIM)596, or an antenna module 597. In one embodiment, at least one (e.g.,the display device 560 or the camera module 580) of the components maybe omitted from the electronic device 501, or one or more othercomponents may be added to the electronic device 501. In one embodiment,some of the components may be implemented as a single integrated circuit(IC). For example, the sensor module 576 (e.g., a fingerprint sensor, aniris sensor, or an illuminance sensor) may be embedded in the displaydevice 560 (e.g., a display).

The processor 520 may execute, for example, software (e.g., a program540) to control at least one other component (e.g., a hardware or asoftware component) of the electronic device 501 coupled with theprocessor 520, and may perform various data processing or computations.As at least part of the data processing or computations, the processor520 may load a command or data received from another component (e.g.,the sensor module 576 or the communication module 590) in volatilememory 532, process the command or the data stored in the volatilememory 532, and store resulting data in non-volatile memory 534. Theprocessor 520 may include a main processor 521 (e.g., a centralprocessing unit (CPU) or an application processor (AP)), and anauxiliary processor 510 (e.g., a graphics processing unit (GPU), animage signal processor (ISP), a sensor hub processor, or a communicationprocessor (CP)) that may be operable independently from, or inconjunction with, the main processor 521. Additionally or alternatively,the auxiliary processor 510 may be adapted to consume less power thanthe main processor 521, or execute a particular function. The auxiliaryprocessor 510 may be implemented as being separate from, or a part of,the main processor 521.

The auxiliary processor 510 may control at least some of the functionsor states related to at least one component (e.g., the display device560, the sensor module 576, or the communication module 590) among thecomponents of the electronic device 501, instead of the main processor521 while the main processor 521 may be in an inactive (e.g., sleep)state, or together with the main processor 521 while the main processor521 may be in an active state (e.g., executing an application).According to one embodiment, the auxiliary processor 510 (e.g., an imagesignal processor or a communication processor) may be implemented aspart of another component (e.g., the camera module 580 or thecommunication module 590) functionally related to the auxiliaryprocessor 510.

The memory 530 may store various data used by at least one component(e.g., the processor 520 or the sensor module 576) of the electronicdevice 501. The various data may include, for example, software (e.g.,the program 540) and input data or output data for a command relatedthereto. The memory 530 may include the volatile memory 532 or thenon-volatile memory 534.

The program 540 may be stored in the memory 530 as software, and mayinclude, for example, an operating system (OS) 542, middleware 544, oran application 546.

The input device 550 may receive a command or data to be used by othercomponent (e.g., the processor 520) of the electronic device 501, fromthe outside (e.g., a user) of the electronic device 501. The inputdevice 550 may include, for example, a microphone, a mouse, or akeyboard.

The sound output device 555 may output sound signals to the outside ofthe electronic device 501. The sound output device 555 may include, forexample, a speaker or a receiver. The speaker may be used for generalpurposes, such as playing multimedia or recording, and the receiver maybe used for receiving an incoming call. According to one embodiment, thereceiver may be implemented as being separate from, or a part of, thespeaker.

The display device 560 may visually provide information to the outside(e.g., a user) of the electronic device 501. The display device 560 mayinclude, for example, a display, a hologram device, or a projector andcontrol circuitry to control a corresponding one of the display,hologram device, and projector. According to one embodiment, the displaydevice 560 may include touch circuitry adapted to detect a touch, orsensor circuitry (e.g., a pressure sensor) adapted to measure theintensity of force incurred by the touch.

The audio module 570 may convert a sound into an electrical signal andvice versa. According to one embodiment, the audio module 570 may obtainthe sound via the input device 550, or output the sound via the soundoutput device 555 or a headphone of an external electronic device 502directly (e.g., wired) or wirelessly coupled with the electronic device501.

The sensor module 576 may detect an operational state (e.g., power ortemperature) of the electronic device 501 or an environmental state(e.g., a state of a user) external to the electronic device 501, andthen generate an electrical signal or data value corresponding to thedetected state. The sensor module 576 may include, for example, agesture sensor, a gyro sensor, an atmospheric pressure sensor, amagnetic sensor, an acceleration sensor, a grip sensor, a proximitysensor, a color sensor, an infrared (IR) sensor, a biometric sensor, atemperature sensor, a humidity sensor, or an illuminance sensor.

The interface 577 may support one or more specified protocols to be usedfor the electronic device 501 to be coupled with the external electronicdevice 502 directly (e.g., wired) or wirelessly. According to oneembodiment, the interface 577 may include, for example, a highdefinition multimedia interface (HDMI), a universal serial bus (USB)interface, a secure digital (SD) card interface, or an audio interface.

A connecting terminal 578 may include a connector via which theelectronic device 501 may be physically connected with the externalelectronic device 502. According to one embodiment, the connectingterminal 578 may include, for example, an HDMI connector, a USBconnector, an SD card connector, or an audio connector (e.g., aheadphone connector).

The haptic module 579 may convert an electrical signal into a mechanicalstimulus (e.g., a vibration or a movement) or an electrical stimuluswhich may be recognized by a user via tactile sensation or kinestheticsensation. According to one embodiment, the haptic module 579 mayinclude, for example, a motor, a piezoelectric element, or an electricalstimulator.

The camera module 580 may capture a still image or moving images.According to one embodiment, the camera module 580 may include one ormore lenses, image sensors, image signal processors, or flashes.

The power management module 588 may manage power supplied to theelectronic device 501. The power management module 588 may beimplemented as at least part of, for example, a power managementintegrated circuit (PMIC).

The battery 589 may supply power to at least one component of theelectronic device 501. According to one embodiment, the battery 589 mayinclude, for example, a primary cell which may be not rechargeable, asecondary cell which may be rechargeable, or a fuel cell.

The communication module 590 may support establishing a direct (e.g.,wired) communication channel or a wireless communication channel betweenthe electronic device 501 and the external electronic device (e.g., theelectronic device 502, the electronic device 504, or the server 508) andperforming communication via the established communication channel. Thecommunication module 590 may include one or more communicationprocessors that are operable independently from the processor 520 (e.g.,the AP) and supports a direct (e.g., wired) communication or a wirelesscommunication. According to one embodiment, the communication module 590may include a wireless communication module 592 (e.g., a cellularcommunication module, a short-range wireless communication module, or aglobal navigation satellite system (GNSS) communication module) or awired communication module 594 (e.g., a local area network (LAN)communication module or a power line communication (PLC) module). Acorresponding one of these communication modules may communicate withthe external electronic device via the first network 598 (e.g., ashort-range communication network, such as Bluetooth™, wireless-fidelity(Wi-Fi) direct, or a standard of the Infrared Data Association (IrDA))or the second network 599 (e.g., a long-range communication network,such as a cellular network, the Internet, or a computer network (e.g.,LAN or wide area network (WAN)). These various types of communicationmodules may be implemented as a single component (e.g., a single IC), ormay be implemented as multiple components (e.g., multiple ICs) that areseparate from each other. The wireless communication module 592 mayidentify and authenticate the electronic device 501 in a communicationnetwork, such as the first network 598 or the second network 599, usingsubscriber information (e.g., international mobile subscriber identity(IMSI)) stored in the subscriber identification module 596.

The antenna module 597 may transmit or receive a signal or power to orfrom the outside (e.g., the external electronic device) of theelectronic device 501. According to one embodiment, the antenna module597 may include one or more antenna ports, and, therefrom, at least oneantenna appropriate for a communication scheme used in the communicationnetwork, such as the first network 598 or the second network 599, may beselected, for example, by the communication module 590 (e.g., thewireless communication module 592). The signal or the power may then betransmitted or received between the communication module 590 and theexternal electronic device via the selected at least one antenna.

At least some of the above-described components may be mutually coupledand communicate signals (e.g., commands or data) therebetween via aninter-peripheral communication scheme (e.g., a bus, a general purposeinput and output (GPIO), a serial peripheral interface (SPI), or amobile industry processor interface (MIPI)).

According to one embodiment, commands or data may be transmitted orreceived between the electronic device 501 and the external electronicdevice 504 via the server 508 coupled with the second network 599. Eachof the electronic devices 502 and 504 may be a device of a same type as,or a different type, from the electronic device 501. All or some ofoperations to be executed at the electronic device 501 may be executedat one or more of the external electronic devices 502, 504, or server508. For example, if the electronic device 501 should perform a functionor a service automatically, or in response to a request from a user oranother device, the electronic device 501, instead of, or in additionto, executing the function or the service, may request the one or moreexternal electronic devices to perform at least part of the function orthe service. The one or more external electronic devices receiving therequest may perform the at least part of the function or the servicerequested, or an additional function or an additional service related tothe request, and transfer an outcome of the performing to the electronicdevice 501. The electronic device 501 may provide the outcome, with orwithout further processing of the outcome, as at least part of a replyto the request. To that end, a cloud computing, distributed computing,or client-server computing technology may be used, for example.

One embodiment may be implemented as software (e.g., the program 540)including one or more instructions that are stored in a storage medium(e.g., internal memory 536 or external memory 538) that may be readableby a machine (e.g., the electronic device 501). For example, a processorof the electronic device 501 may invoke at least one of the one or moreinstructions stored in the storage medium, and execute it, with orwithout using one or more other components under the control of theprocessor. Thus, a machine may be operated to perform at least onefunction according to the at least one instruction invoked. The one ormore instructions may include code generated by a complier or codeexecutable by an interpreter. A machine-readable storage medium may beprovided in the form of a non-transitory storage medium. The term“non-transitory” indicates that the storage medium may be a tangibledevice, and does not include a signal (e.g., an electromagnetic wave),but this term does not differentiate between where data may besemi-permanently stored in the storage medium and where the data may betemporarily stored in the storage medium.

According to one embodiment, a method of the disclosure may be includedand provided in a computer program product. The computer program productmay be traded as a product between a seller and a buyer. The computerprogram product may be distributed in the form of a machine-readablestorage medium (e.g., a compact disc read only memory (CD-ROM)), or bedistributed (e.g., downloaded or uploaded) online via an applicationstore (e.g., Play Store), or between two user devices (e.g., smartphones) directly. If distributed online, at least part of the computerprogram product may be temporarily generated or at least temporarilystored in the machine-readable storage medium, such as memory of themanufacturer's server, a server of the application store, or a relayserver.

According to one embodiment, each component (e.g., a module or aprogram) of the above-described components may include a single entityor multiple entities. One or more of the above-described components maybe omitted, or one or more other components may be added. Alternativelyor additionally, a plurality of components (e.g., modules or programs)may be integrated into a single component. In this case, the integratedcomponent may still perform one or more functions of each of theplurality of components in the same or similar manner as they areperformed by a corresponding one of the plurality of components beforethe integration. Operations performed by the module, the program, oranother component may be carried out sequentially, in parallel,repeatedly, or heuristically, or one or more of the operations may beexecuted in a different order or omitted, or one or more otheroperations may be added.

Although certain embodiments of the present disclosure have beendescribed in the detailed description of the present disclosure, thepresent disclosure may be modified in various forms without departingfrom the scope of the present disclosure. Thus, the scope of the presentdisclosure shall not be determined merely based on the describedembodiments, but rather determined based on the accompanying claims andequivalents thereto.

What is claimed is:
 1. A method comprising: inputting precoding matrixindicator (PMI) data and sounding reference signal (SRS) data from auser equipment (UE); and composing a channel state, including abeamforming matrix, using the input PMI data and SRS data.
 2. The methodof claim 1, wherein the PMI data is feedback data generated in responseto receiving channel state information (CSI) data.
 3. The method ofclaim 1, wherein the composed channel state supports communicationsbetween a base station and the UE.
 4. The method of claim 1, wherein thePMI data is generated using one or more PMI codebooks.
 5. The method ofclaim 4, wherein generating the PMI data further comprises quantizingbeamforming data using the one or more PMI codebooks.
 6. The method ofclaim 1, wherein the SRS data is derived based at least in part ondownlink channel reciprocity.
 7. The method of claim 1, wherein the SRSdata is derived based at least in part on uplink channel reciprocity. 8.The method of claim 1, where in the channel state relates to abeamforming configuration utilized by a device including multiple inputand multiple output antennas.
 9. The method of claim 1, whereincomposing the channel state including the beamforming matrix is based atleast in part on channel multiplexing of the input data.
 10. The methodof claim 1, wherein the input SRS data is partial channel estimationdata derived from SRS switching.
 11. The method of claim 1, furthercomprising composing intermediate SRS channel data based on the inputSRS data, wherein the beamforming matrix is composed based on thecomposed SRS channel data.
 12. A system comprising: a processor; and amemory storing non-transitory processor-executable instructions that,when executed by the processor, cause the processor to: input precodingmatrix indicator (PMI) data and sounding reference signal (SRS) datafrom a user equipment (UE); and compose a channel state, including abeamforming matrix, using the input PMI data and SRS data.
 13. Thesystem of claim 12, wherein the PMI data is feedback data generated inresponse to receiving channel state information (CSI) data.
 14. Thesystem of claim 12, wherein the composed channel state supportscommunications between a base station and the UE.
 15. The system ofclaim 12, wherein the PMI data is generated using one or more PMIcodebooks.
 16. The system of claim 15, wherein generating the PMI datafurther comprises quantizing beamforming data using the one or more PMIcodebooks.
 17. The system of claim 12, wherein the SRS data is derivedbased at least in part on downlink channel reciprocity.
 18. Anon-transitory computer-readable medium comprising instructions forderiving a beamforming matrix, wherein execution of the instructions byone or more processors causes the one or more processors to carry outthe steps of: inputting precoding matrix indicator (PMI) data andsounding reference signal (SRS) data from a user equipment (UE); andcomposing a channel state, including a beamforming matrix, using theinput PMI data and SRS data.
 19. The non-transitory computer-readablemedium of claim 18, wherein the PMI data is feedback data generated inresponse to receiving channel state information (CSI) data.
 20. Thenon-transitory computer-readable medium of claim 18, wherein thecomposed channel state supports communications between a base stationand the UE.